Pregnancy is typicawwy divided into dree trimesters.[4] The first trimester is from week one drough 12 and incwudes conception, which is when de sperm fertiwizes de egg.[4] The fertiwized egg den travews down de fawwopian tube and attaches to de inside of de uterus, where it begins to form de embryo and pwacenta.[4] During de first trimester, de possibiwity of miscarriage (naturaw deaf of embryo or fetus) is at its highest.[2] The second trimester is from week 13 drough 28.[4] Around de middwe of de second trimester, movement of de fetus may be fewt.[4] At 28 weeks, more dan 90% of babies can survive outside of de uterus if provided wif high-qwawity medicaw care.[4] The dird trimester is from 29 weeks drough 40 weeks.[4]

Terminowogy

Associated terms for pregnancy are gravid and parous. Gravidus and gravid come from de Latin for "heavy" and a pregnant femawe is sometimes referred to as a gravida.[19]Gravidity is a term used to describe de number of times dat a femawe has been pregnant. Simiwarwy, de term parity is used for de number of times dat a femawe carries a pregnancy to a viabwe stage.[20] Twins and oder muwtipwe birds are counted as one pregnancy and birf. A woman who has never been pregnant is referred to as a nuwwigravida. A woman who is (or has been onwy) pregnant for de first time is referred to as a primigravida,[21] and a woman in subseqwent pregnancies as a muwtigravida or as muwtiparous.[19][22] Therefore, during a second pregnancy a woman wouwd be described as gravida 2, para 1 and upon wive dewivery as gravida 2, para 2. In-progress pregnancies, abortions, miscarriages and/or stiwwbirds account for parity vawues being wess dan de gravida number. In de case of a muwtipwe birf de gravida number and parity vawue are increased by one onwy. Women who have never carried a pregnancy achieving more dan 20 weeks of gestation age are referred to as nuwwiparous.[23]

The terms preterm and postterm have wargewy repwaced earwier terms of premature and postmature. Preterm and postterm are defined above, whereas premature and postmature have historicaw meaning and rewate more to de infant's size and state of devewopment rader dan to de stage of pregnancy.[24][25]

Breast tenderness is common during de first trimester, and is more common in women who are pregnant at a young age.[28]

Chronowogy

The chronowogy of pregnancy is, unwess oderwise specified, generawwy given as gestationaw age, where de starting point is de woman's wast menstruaw period (LMP), or de corresponding age of de gestation as estimated by a more accurate medod if avaiwabwe. Sometimes, timing may awso use de fertiwization age which is de age of de embryo.

Earwy obstetric uwtrasound, comparing de size of an embryo or fetus to dat of a reference group of pregnancies of known gestationaw age (such as cawcuwated from wast menstruaw periods), and using de mean gestationaw age of oder embryos or fetuses of de same size. If de gestationaw age as cawcuwated from an earwy uwtrasound is contradictory to de one cawcuwated directwy from de wast menstruaw period, it is stiww de one from de earwy uwtrasound dat is used for de rest of de pregnancy.[29]

Estimation of due date

Distribution of gestationaw age at chiwdbirf among singweton wive birds, given bof when gestationaw age is estimated by first trimester uwtrasound and directwy by wast menstruaw period.[31] Roughwy 80% of birds occur between 37 and 41 weeks of gestationaw age.

Determination of which time point is to be used as origin for gestationaw age, as described in section above.

Adding de estimated gestationaw age at chiwdbirf to de above time point. Chiwdbirf on average occurs at a gestationaw age of 280 days (40 weeks), which is derefore often used as a standard estimation for individuaw pregnancies.[32] However, awternative durations as weww as more individuawized medods have awso been suggested.

Naegewe's ruwe is a standard way of cawcuwating de due date for a pregnancy when assuming a gestationaw age of 280 days at chiwdbirf. The ruwe estimates de expected date of dewivery (EDD) by adding a year, subtracting dree monds, and adding seven days to de origin of gestationaw age. Awternativewy dere are mobiwe apps, which essentiawwy awways give consistent estimations compared to each oder and correct for weap year, whiwe pregnancy wheews made of paper can differ from each oder by 7 days and generawwy do not correct for weap year.[33]

Furdermore, actuaw chiwdbirf has onwy a certain probabiwity of occurring widin de wimits of de estimated due date. A study of singweton wive birds came to de resuwt dat chiwdbirf has a standard deviation of 14 days when gestationaw age is estimated by first trimester uwtrasound, and 16 days when estimated directwy by wast menstruaw period.[31]

Fertiwization (conception) is sometimes used as de initiation of pregnancy, wif de derived age being termed fertiwization age. Fertiwization usuawwy occurs about two weeks before de next expected menstruaw period.

A dird point in time is awso considered by some peopwe to be de true beginning of a pregnancy: This is time of impwantation, when de future fetus attaches to de wining of de uterus. This is about a week to ten days after fertiwization, uh-hah-hah-hah.[35] In dis modew, during de time between conception and impwantation, de future fetus exists, but de woman is not considered pregnant.

Devewopment of embryo and fetus

The sperm and de egg ceww, which has been reweased from one of de femawe's two ovaries, unite in one of de two fawwopian tubes. The fertiwized egg, known as a zygote, den moves toward de uterus, a journey dat can take up to a week to compwete. Ceww division begins approximatewy 24 to 36 hours after de mawe and femawe cewws unite. Ceww division continues at a rapid rate and de cewws den devewop into what is known as a bwastocyst. The bwastocyst arrives at de uterus and attaches to de uterine waww, a process known as impwantation.

The devewopment of de mass of cewws dat wiww become de infant is cawwed embryogenesis during de first approximatewy ten weeks of gestation, uh-hah-hah-hah. During dis time, cewws begin to differentiate into de various body systems. The basic outwines of de organ, body, and nervous systems are estabwished. By de end of de embryonic stage, de beginnings of features such as fingers, eyes, mouf, and ears become visibwe. Awso during dis time, dere is devewopment of structures important to de support of de embryo, incwuding de pwacenta and umbiwicaw cord. The pwacenta connects de devewoping embryo to de uterine waww to awwow nutrient uptake, waste ewimination, and gas exchange via de moder's bwood suppwy. The umbiwicaw cord is de connecting cord from de embryo or fetus to de pwacenta.

After about ten weeks of gestationaw age, de embryo becomes known as a fetus. At de beginning of de fetaw stage, de risk of miscarriage decreases sharpwy.[36] At dis stage, a fetus is about 30 mm (1.2 inches) in wengf, de heartbeat is seen via uwtrasound, and de fetus makes invowuntary motions.[37] During continued fetaw devewopment, de earwy body systems, and structures dat were estabwished in de embryonic stage continue to devewop. Sex organs begin to appear during de dird monf of gestation, uh-hah-hah-hah. The fetus continues to grow in bof weight and wengf, awdough de majority of de physicaw growf occurs in de wast weeks of pregnancy.

Ewectricaw brain activity is first detected between de fiff and sixf week of gestation, uh-hah-hah-hah. It is considered primitive neuraw activity rader dan de beginning of conscious dought. Synapses begin forming at 17 weeks, and begin to muwtipwy qwickwy at week 28 untiw 3 to 4 monds after birf.[38]

Embryo at 4 weeks after fertiwization, uh-hah-hah-hah. (Gestationaw age of 6 weeks.)

Fetus at 8 weeks after fertiwization, uh-hah-hah-hah. (Gestationaw age of 10 weeks.)

Fetus at 18 weeks after fertiwization, uh-hah-hah-hah. (Gestationaw age of 20 weeks.)

Fetus at 38 weeks after fertiwization, uh-hah-hah-hah. (Gestationaw age of 40 weeks.)

The fetus is geneticawwy different from de woman and can be viewed as an unusuawwy successfuw awwograft.[39] The main reason for dis success is increased immune towerance during pregnancy.[40] Immune towerance is de concept dat de body is abwe to not mount an immune system response against certain triggers.[39]

Pregnancy is typicawwy broken into dree periods, or trimesters, each of about dree monds.[41][42] Each trimester is defined as 14 weeks, for a totaw duration of 42 weeks, awdough de average duration of pregnancy is 40 weeks.[43]

Second trimester

By de end of de second trimester, de expanding uterus has created a visibwe "baby bump". Awdough de breasts have been devewoping internawwy since de beginning of de pregnancy, most of de visibwe changes appear after dis point.

Weeks 13 to 28 of de pregnancy are cawwed de second trimester. Most women feew more energized in dis period, and begin to put on weight as de symptoms of morning sickness subside and eventuawwy fade away. The uterus, de muscuwar organ dat howds de devewoping fetus, can expand up to 20 times its normaw size during pregnancy.

Awdough de fetus begins to move during de first trimester, it is not untiw de second trimester dat movement, known as qwickening, can be fewt. This typicawwy happens in de fourf monf, more specificawwy in de 20f to 21st week, or by de 19f week if de woman has been pregnant before. It is common for some women not to feew de fetus move untiw much water. During de second trimester, most women begin to wear maternity cwodes.

Third trimester

Pregnant woman in dird trimester of pregnancy (wast monf)

The uterus expands making up a warger and warger portion of de woman's abdomen, uh-hah-hah-hah. At weft anterior view wif monds wabewed, at right wateraw view wabewing de wast 4 weeks. During de finaw stages of gestation before chiwdbirf de fetus and uterus wiww drop to a wower position, uh-hah-hah-hah.

Finaw weight gain takes pwace, which is de most weight gain droughout de pregnancy. The woman's abdomen wiww transform in shape as it drops due to de fetus turning in a downward position ready for birf. During de second trimester, de woman's abdomen wouwd have been upright, whereas in de dird trimester it wiww drop down wow. The fetus moves reguwarwy, and is fewt by de woman, uh-hah-hah-hah. Fetaw movement can become strong and be disruptive to de woman, uh-hah-hah-hah. The woman's navew wiww sometimes become convex, "popping" out, due to de expanding abdomen.

Head engagement, where de fetaw head descends into cephawic presentation, rewieves pressure on de upper abdomen wif renewed ease in breading. It awso severewy reduces bwadder capacity, and increases pressure on de pewvic fwoor and de rectum.

It is awso during de dird trimester dat maternaw activity and sweep positions may affect fetaw devewopment due to restricted bwood fwow. For instance, de enwarged uterus may impede bwood fwow by compressing de vena cava when wying fwat, which is rewieved by wying on de weft side.[46]

Chiwdbirf

Chiwdbirf, referred to as wabor and dewivery in de medicaw fiewd, is de process whereby an infant is born, uh-hah-hah-hah.[47]

A woman is considered to be in wabour when she begins experiencing reguwar uterine contractions, accompanied by changes of her cervix – primariwy effacement and diwation, uh-hah-hah-hah. Whiwe chiwdbirf is widewy experienced as painfuw, some women do report painwess wabours, whiwe oders find dat concentrating on de birf hewps to qwicken wabour and wessen de sensations. Most birds are successfuw vaginaw birds, but sometimes compwications arise and a woman may undergo a cesarean section.

During de time immediatewy after birf, bof de moder and de baby are hormonawwy cued to bond, de moder drough de rewease of oxytocin, a hormone awso reweased during breastfeeding. Studies show dat skin-to-skin contact between a moder and her newborn immediatewy after birf is beneficiaw for bof de moder and baby. A review done by de Worwd Heawf Organization found dat skin-to-skin contact between moders and babies after birf reduces crying, improves moder–infant interaction, and hewps moders to breastfeed successfuwwy. They recommend dat neonates be awwowed to bond wif de moder during deir first two hours after birf, de period dat dey tend to be more awert dan in de fowwowing hours of earwy wife.[48]

In de ideaw chiwdbirf wabor begins on its own when a woman is "at term".[14]
Events before compwetion of 37 weeks are considered preterm.[49]Preterm birf is associated wif a range of compwications and shouwd be avoided if possibwe.[51]

Sometimes if a woman's water breaks or she has contractions before 39 weeks, birf is unavoidabwe.[50] However, spontaneous birf after 37 weeks is considered term and is not associated wif de same risks of a pre-term birf.[47] Pwanned birf before 39 weeks by Caesarean section or wabor induction, awdough "at term", resuwts in an increased risk of compwications.[52] This is from factors incwuding underdevewoped wungs of newborns, infection due to underdevewoped immune system, feeding probwems due to underdevewoped brain, and jaundice from underdevewoped wiver.[53]

Babies born between 39 and 41 weeks gestation have better outcomes dan babies born eider before or after dis range.[50] This speciaw time period is cawwed "fuww term".[50] Whenever possibwe, waiting for wabor to begin on its own in dis time period is best for de heawf of de moder and baby.[14] The decision to perform an induction must be made after weighing de risks and benefits, but is safer after 39 weeks.[14]

Events after 42 weeks are considered postterm.[50] When a pregnancy exceeds 42 weeks, de risk of compwications for bof de woman and de fetus increases significantwy.[54][55] Therefore, in an oderwise uncompwicated pregnancy, obstetricians usuawwy prefer to induce wabour at some stage between 41 and 42 weeks.[56]

Postnataw period

The postnataw period, awso referred to as de puerperium, begins immediatewy after dewivery and extends for about six weeks.[47] During dis period, de moder's body begins de return to pre-pregnancy conditions dat incwudes changes in hormone wevews and uterus size.[47]

Diagnosis

The beginning of pregnancy may be detected eider based on symptoms by de woman hersewf, or by using pregnancy tests. However, an important condition wif serious heawf impwications dat is qwite common is de deniaw of pregnancy by de pregnant woman, uh-hah-hah-hah. About one in 475 deniaws wiww wast untiw around de 20f week of pregnancy. The proportion of cases of deniaw, persisting untiw dewivery is about 1 in 2500.[57] Conversewy, some non-pregnant women have a very strong bewief dat dey are pregnant awong wif some of de physicaw changes. This condition is known as a fawse pregnancy.[58]

Biomarkers

Pregnancy detection can be accompwished using one or more various pregnancy tests,[63] which detect hormones generated by de newwy formed pwacenta, serving as biomarkers of pregnancy.[64] Bwood and urine tests can detect pregnancy 12 days after impwantation, uh-hah-hah-hah.[65] Bwood pregnancy tests are more sensitive dan urine tests (giving fewer fawse negatives).[66] Home pregnancy tests are urine tests, and normawwy detect a pregnancy 12 to 15 days after fertiwization, uh-hah-hah-hah.[67] A qwantitative bwood test can determine approximatewy de date de embryo was conceived because HCG doubwes every 36 to 48 hours.[47] A singwe test of progesterone wevews can awso hewp determine how wikewy a fetus wiww survive in dose wif a dreatened miscarriage (bweeding in earwy pregnancy).[68]

Management

Fwowchart showing de recommended weight wimits for wifting at work during pregnancy as a function of wifting freqwency, weeks of gestation, and de position of de wifted object rewative to de wifter's body.[72]

Prenataw care

Pre-conception counsewing is care dat is provided to a woman and/ or coupwe to discuss conception, pregnancy, current heawf issues and recommendations for de period before pregnancy.[73]

Prenataw medicaw care is de medicaw and nursing care recommended for women during pregnancy, time intervaws and exact goaws of each visit differ by country.[74] Women who are high risk have better outcomes if dey are seen reguwarwy and freqwentwy by a medicaw professionaw dan women who are wow risk.[75] A woman can be wabewed as high risk for different reasons incwuding previous compwications in pregnancy, compwications in de current pregnancy, current medicaw diseases, or sociaw issues.[76][77]

The aim of good prenataw care is prevention, earwy identification, and treatment of any medicaw compwications.[78] A basic prenataw visit consists of measurement of bwood pressure, fundaw height, weight and fetaw heart rate, checking for symptoms of wabor, and guidance for what to expect next.[73]

Nutrition

Nutrition during pregnancy is important to ensure heawdy growf of de fetus.[79] Nutrition during pregnancy is different from de non-pregnant state.[79] There are increased energy reqwirements and specific micronutrient reqwirements.[79] Women benefit from education to encourage a bawanced energy and protein intake during pregnancy.[80] Some women may need professionaw medicaw advice if deir diet is affected by medicaw conditions, food awwergies, or specific rewigious/ edicaw bewiefs.[81]

Adeqwate periconceptionaw (time before and right after conception) fowic acid (awso cawwed fowate or Vitamin B9) intake has been shown to decrease de risk of fetaw neuraw tube defects, such as spina bifida.[82] The neuraw tube devewops during de first 28 days of pregnancy, a urine pregnancy test is not usuawwy positive untiw 14 days post-conception, expwaining de necessity to guarantee adeqwate fowate intake before conception, uh-hah-hah-hah.[67][83] Fowate is abundant in green weafy vegetabwes, wegumes, and citrus.[84] In de United States and Canada, most wheat products (fwour, noodwes) are fortified wif fowic acid.[85]

DHA omega-3 is a major structuraw fatty acid in de brain and retina, and is naturawwy found in breast miwk.[86] It is important for de woman to consume adeqwate amounts of DHA during pregnancy and whiwe nursing to support her weww-being and de heawf of her infant.[86] Devewoping infants cannot produce DHA efficientwy, and must receive dis vitaw nutrient from de woman drough de pwacenta during pregnancy and in breast miwk after birf.[87]

Severaw micronutrients are important for de heawf of de devewoping fetus, especiawwy in areas of de worwd where insufficient nutrition is common, uh-hah-hah-hah.[10] Women wiving in wow and middwe income countries are suggested to take muwtipwe micronutrient suppwements containing iron and fowic acid.[10] These suppwements have been shown to improve birf outcomes in devewoping countries, but do not have an effect on perinataw mortawity.[10][88] Adeqwate intake of fowic acid, and iron is often recommended.[89][90] In devewoped areas, such as Western Europe and de United States, certain nutrients such as Vitamin D and cawcium, reqwired for bone devewopment, may awso reqwire suppwementation, uh-hah-hah-hah.[91][92][93] Vitamin E suppwementation has not been shown to improve birf outcomes.[94] Zinc suppwementation has been associated wif a decrease in preterm birf, but it is uncwear wheder it is causative.[95] Daiwy iron suppwementation reduces de risk of maternaw anemia.[96] Studies of routine daiwy iron suppwementation for pregnant women found improvement in bwood iron wevews, widout a cwear cwinicaw benefit.[97] The nutritionaw needs for women carrying twins or tripwets are higher dan dose of women carrying one baby.[98]

Women are counsewed to avoid certain foods, because of de possibiwity of contamination wif bacteria or parasites dat can cause iwwness.[99] Carefuw washing of fruits and raw vegetabwes may remove dese padogens, as may doroughwy cooking weftovers, meat, or processed meat.[100] Unpasteurized dairy and dewi meats may contain Listeria, which can cause neonataw meningitis, stiwwbirf and miscarriage.[101] Pregnant women are awso more prone to Sawmonewwa infections, can be in eggs and pouwtry, which shouwd be doroughwy cooked.[102] Cat feces and undercooked meats may contain de parasite Toxopwasma gondii and can cause toxopwasmosis.[100] Practicing good hygiene in de kitchen can reduce dese risks.[103]

Women are awso counsewed to eat seafood in moderation and to ewiminate seafood known to be high in mercury because of de risk of birf defects.[102] Pregnant women are counsewed to consume caffeine in moderation, because warge amounts of caffeine are associated wif miscarriage.[47] However, de rewationship between caffeine, birdweight, and preterm birf is uncwear.[104]

Weight gain

The amount of heawdy weight gain during a pregnancy varies.[105] Weight gain is rewated to de weight of de baby, de pwacenta, extra circuwatory fwuid, warger tissues, and fat and protein stores.[79] Most needed weight gain occurs water in pregnancy.[106]

The Institute of Medicine recommends an overaww pregnancy weight gain for dose of normaw weight (body mass index of 18.5–24.9), of 11.3–15.9 kg (25–35 pounds) having a singweton pregnancy.[107] Women who are underweight (BMI of wess dan 18.5), shouwd gain between 12.7–18 kg (28–40 wbs), whiwe dose who are overweight (BMI of 25–29.9) are advised to gain between 6.8–11.3 kg (15–25 wbs) and dose who are obese (BMI>30) shouwd gain between 5–9 kg (11–20 wbs).[108] These vawues reference de expectations for a term pregnancy.

Around 50% of women of chiwdbearing age in devewoped countries wike de United Kingdom are overweight or obese before pregnancy.[109] Diet modification is de most effective way to reduce weight gain and associated risks in pregnancy.[109] A diet dat has foods wif a wow gwycemic index may hewp prevent de onset of gestationaw diabetes.[110][needs update]

Medication

Drugs used during pregnancy can have temporary or permanent effects on de fetus.[111] Anyding (incwuding drugs) dat can cause permanent deformities in de fetus are wabewed as teratogens.[112] In de U.S., drugs were cwassified into categories A, B, C, D and X based on de Food and Drug Administration (FDA) rating system to provide derapeutic guidance based on potentiaw benefits and fetaw risks.[113] Drugs, incwuding some muwtivitamins, dat have demonstrated no fetaw risks after controwwed studies in humans are cwassified as Category A.[111] On de oder hand, drugs wike dawidomide wif proven fetaw risks dat outweigh aww benefits are cwassified as Category X.[111]

Pregnant women can awso be exposed to toxins in de workpwace, incwuding airborne particwes. The effects of wearing N95 fiwtering facepiece respirators are simiwar for pregnant women as for non-pregnant women, and wearing a respirator for one hour does not affect de fetaw heart rate.[122]

Sexuaw activity

Most women can continue to engage in sexuaw activity droughout pregnancy.[123] Most research suggests dat during pregnancy bof sexuaw desire and freqwency of sexuaw rewations decrease.[124][125] In context of dis overaww decrease in desire, some studies indicate a second-trimester increase, preceding a decrease during de dird trimester.[126][127]

Sex during pregnancy is a wow-risk behavior except when de heawdcare provider advises dat sexuaw intercourse be avoided for particuwar medicaw reasons.[123] For a heawdy pregnant woman, dere is no safe or right way to have sex during pregnancy.[123] Pregnancy awters de vaginaw fwora wif a reduction in microscopic species/genus diversity.[128]

The Cwinicaw Practice Obstetrics Committee of Canada recommends dat "Aww women widout contraindications shouwd be encouraged to participate in aerobic and strengf-conditioning exercises as part of a heawdy wifestywe during deir pregnancy".[132] Awdough an upper wevew of safe exercise intensity has not been estabwished, women who were reguwar exercisers before pregnancy and who have uncompwicated pregnancies shouwd be abwe to engage in high intensity exercise programs.[132] In generaw, participation in a wide range of recreationaw activities appears to be safe, wif de avoidance of dose wif a high risk of fawwing such as horseback riding or skiing or dose dat carry a risk of abdominaw trauma, such as soccer or hockey.[133]

The American Cowwege of Obstetricians and Gynecowogists reports dat in de past, de main concerns of exercise in pregnancy were focused on de fetus and any potentiaw maternaw benefit was dought to be offset by potentiaw risks to de fetus. However, dey write dat more recent information suggests dat in de uncompwicated pregnancy, fetaw injuries are highwy unwikewy.[133] They do, however, wist severaw circumstances when a woman shouwd contact her heawf care provider before continuing wif an exercise program: vaginaw bweeding, dyspnea before exertion, dizziness, headache, chest pain, muscwe weakness, preterm wabor, decreased fetaw movement, amniotic fwuid weakage, and cawf pain or swewwing (to ruwe out drombophwebitis).[133]

Sweep

It has been suggested dat shift work and exposure to bright wight at night shouwd be avoided at weast during de wast trimester of pregnancy to decrease de risk of psychowogicaw and behavioraw probwems in de newborn, uh-hah-hah-hah.[134]

Thyroid disease in pregnancy can, if uncorrected, cause adverse effects on fetaw and maternaw weww-being. The deweterious effects of dyroid dysfunction can awso extend beyond pregnancy and dewivery to affect neurointewwectuaw devewopment in de earwy wife of de chiwd. Demand for dyroid hormones is increased during pregnancy, which may cause a previouswy unnoticed dyroid disorder to worsen, uh-hah-hah-hah.

Epidemiowogy

About 213 miwwion pregnancies occurred in 2012 of which 190 miwwion were in de devewoping worwd and 23 miwwion were in de devewoped worwd.[11] This is about 133 pregnancies per 1,000 women between de ages of 15 and 44.[11] About 10% to 15% of recognized pregnancies end in miscarriage.[2] Gwobawwy, 44% of pregnancies are unpwanned. Over hawf (56%) of unpwanned pregnancies are aborted. In countries where abortion is prohibited, or onwy carried out in circumstances where de moder's wife is at risk, 48% of unpwanned pregnancies are aborted iwwegawwy. Compared to de rate in countries where abortion is wegaw, at 69%.[17]

Of pregnancies in 2012, 120 miwwion occurred in Asia, 54 miwwion in Africa, 19 miwwion in Europe, 18 miwwion in Latin America and de Caribbean, 7 miwwion in Norf America, and 1 miwwion in Oceania.[11] Pregnancy rates are 140 per 1000 women of chiwdbearing age in de devewoping worwd and 94 per 1000 in de devewoped worwd.[11]

The rate of pregnancy, as weww as de ages at which it occurs, differ by country and region, uh-hah-hah-hah. It is infwuenced by a number of factors, such as cuwturaw, sociaw and rewigious norms; access to contraception; and rates of education, uh-hah-hah-hah. The totaw fertiwity rate (TFR) in 2013 was estimated to be highest in Niger (7.03 chiwdren/woman) and wowest in Singapore (0.79 chiwdren/woman).[147]

In Europe, de average chiwdbearing age has been rising continuouswy for some time. In Western, Nordern, and Soudern Europe, first-time moders are on average 26 to 29 years owd, up from 23 to 25 years at de start of de 1970s. In a number of European countries (Spain), de mean age of women at first chiwdbirf has crossed de 30-year dreshowd.

This process is not restricted to Europe. Asia, Japan and de United States are aww seeing average age at first birf on de rise, and increasingwy de process is spreading to countries in de devewoping worwd wike China, Turkey and Iran, uh-hah-hah-hah. In de US, de average age of first chiwdbirf was 25.4 in 2010.[148]

Society and cuwture

In most cuwtures, pregnant women have a speciaw status in society and receive particuwarwy gentwe care.[151] At de same time, dey are subject to expectations dat may exert great psychowogicaw pressure, such as having to produce a son and heir. In many traditionaw societies, pregnancy must be preceded by marriage, on pain of ostracism of moder and (iwwegitimate) chiwd.

Overaww, pregnancy is accompanied by numerous customs dat are often subject to ednowogicaw research, often rooted in traditionaw medicine or rewigion, uh-hah-hah-hah. The baby shower is an exampwe of a modern custom.

Pregnancy is an important topic in sociowogy of de famiwy. The prospective chiwd may prewiminariwy be pwaced into numerous sociaw rowes. The parents' rewationship and de rewation between parents and deir surroundings are awso affected.

Arts

Images of pregnant women, especiawwy smaww figurines, were made in traditionaw cuwtures in many pwaces and periods, dough it is rarewy one of de most common types of image. These incwude ceramic figures from some Pre-Cowumbian cuwtures, and a few figures from most of de ancient Mediterranean cuwtures. Many of dese seem to be connected wif fertiwity. Identifying wheder such figures are actuawwy meant to show pregnancy is often a probwem, as weww as understanding deir rowe in de cuwture concerned.

Among de owdest surviving exampwes of de depiction of pregnancy are prehistoric figurines found across much of Eurasia and cowwectivewy known as Venus figurines. Some of dese appear to be pregnant.

The unhappy scene usuawwy cawwed Diana and Cawwisto, showing de moment of discovery of Cawwisto's forbidden pregnancy, is sometimes painted from de Renaissance onwards. Graduawwy, portraits of pregnant women began to appear, wif a particuwar fashion for "pregnancy portraits" in ewite portraiture of de years around 1600.

Pregnancy, and especiawwy pregnancy of unmarried women, is awso an important motif in witerature. Notabwe exampwes incwude Hardy's Tess of de d'Urberviwwes and Goede's Faust.

Abortion

An abortion is de termination of an embryo or fetus, eider naturawwy or via medicaw medods.[153] When done ewectivewy, it is more often done widin de first trimester dan de second, and rarewy in de dird.[36] Not using contraception, contraceptive faiwure, poor famiwy pwanning or rape can wead to undesired pregnancies. Legawity of sociawwy indicated abortions varies widewy bof internationawwy and drough time. In most countries of Western Europe, abortions during de first trimester were a criminaw offense a few decades ago[when?] but have since been wegawized, sometimes subject to mandatory consuwtations. In Germany, for exampwe, as of 2009 wess dan 3% of abortions had a medicaw indication, uh-hah-hah-hah.

Legaw protection

Many countries have various wegaw reguwations in pwace to protect pregnant women and deir chiwdren, uh-hah-hah-hah. Maternity Protection Convention ensures dat pregnant women are exempt from activities such as night shifts or carrying heavy stocks. Maternity weave typicawwy provides paid weave from work during roughwy de wast trimester of pregnancy and for some time after birf. Notabwe extreme cases incwude Norway (8 monds wif fuww pay) and de United States (no paid weave at aww except in some states). Moreover, many countries have waws against pregnancy discrimination.

In de United States, some actions dat resuwt in miscarriage or stiwwbirf are considered crimes. One waw dat does so is de federaw Unborn Victims of Viowence Act. In 2014, de American state of Tennessee passed a waw which awwows prosecutors to charge a woman wif criminaw assauwt if she uses iwwegaw drugs during her pregnancy and her fetus or newborn is considered harmed as a resuwt.[154]

^ abcInstitute for Quawity and Efficiency in Heawf Care. "Weight gain in pregnancy". Fact sheet. Institute for Quawity and Efficiency in Heawf Care. Archived from de originaw on 14 December 2013. Retrieved 23 June 2013.